Demonic Flute (Shinobi World Supplement)
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Weapon (club), Rare (requires attunement)
Forged from chakra-infused metal, this flute is as deadly as a melee weapon as it is as an instrument. You gain a +1 bonus to attack and damage rolls made with this magic weapon.
When you cast a genjutsu while attuned to a demonic flute, you may spend 4 chakra to make it an auditory genjutsu. An auditory genjutsu effects every creature within 5 ft. of the targeted area, and only effects creatures that are not deafened.
If you may cast auditory genjutsu in any other way, its range and effected radius from being an auditory genjutsu are doubled.